Charge Air Intercooler

ABSTRACT

The invention relates to a charge air intercooler ( 1 ), in particular for a private car, in which charge air can be cooled by a coolant flowing through flow channels, whereby the flow channels for the coolant are formed from flat tubes ( 6 ).

The invention relates to a charge air intercooler according to the preamble of claim 1.

In order to increase engine performance, turbochargers are used for the purpose of compressing the air. In this case, however, the air, referred to hereinbelow as charge air, is heated to temperatures of above 150° C. as a result of the compression in the turbocharger. In order to reduce such air heating, use is made of air coolers which are arranged at the front of the cooling module and serve for cooling the charge air. The charge air here flows through a heat-transfer means which has ambient air flowing through it in order to cool it.

This allows the charge air to be cooled to a temperature of approximately 10-90 K above the temperature of the ambient air. The cooling of the charge air makes it possible to increase the engine performance.

In order to allow improved cooling, use is being made more and more, in the case of passenger vehicles, of coolant-cooled charge air intercoolers. In the case of compressor charging, and to some extent also in the case of turbocharging, these charge air intercoolers are arranged directly in the intake region (and/or in the compressor housing). An example of such a known charge air intercooler is illustrated in detail form in section in FIG. 4. The charge air intercooler comprises a plurality of metal plates and profiled elements which are connected to form flow channels for the coolant and have their ends projecting into collector tanks. Between the flow channels for the coolant, the charge air which is to be cooled flows transversely to the flow direction of the coolant in the flow channels. On account of the high weight and of the relatively complex production, however, these charge air intercoolers are expensive. Furthermore, the transfer of heat leaves something to be desired.

Taking this prior art as the departure point, it is an object of the invention to provide an improved charge air intercooler. This object is achieved by a charge air intercooler having the features of claim 1. Advantageous configurations form the subject matter of the subclaims.

The invention provides a charge air intercooler, in particular for a passenger vehicle, in which charge air can be cooled by a coolant flowing in flow channels, the flow channels for the coolant being formed by flat tubes. In contrast to conventional charge air intercoolers, the use of flat tubes reduces the number of parts required, in which case more straightforward production is possible.

The flat tubes are preferably arranged in at least one row. In this case, the coolant flow is preferably deflected over the width and/or the depth of the charge air intercooler.

In order for a high level of efficiency to be made possible, the ratio of charge air channel height to coolant channel height is preferably 1:1 to 4:1, in particular 2:1 to 3:1. In another advantageous configuration, the ratio of charge air channel height to coolant channel height is 1:1 to 10:1, in particular 2:1 to 8:1.

In order to improve the heat transfer, preferably at least two rows of flat tubes are provided, and flow can take place through these in crosscurrent operation or in cross-counter current operation in relation to the charge air which is to be cooled. As an alternative, flow can take place through individual chambers of the flat tubes in crosscurrent operation, in particular if just one row of flat tubes is provided.

Production is additionally simplified in that the individual components of the charge air intercooler including the coolant tanks are soldered together, soldering preferably taking place in one operation.

Turbulence inserts are preferably arranged in the flat tubes in order to mix the coolant and thus to improve the exchange of heat.

The flat tubes terminate in at least one collector tank, and this may preferably be a deep-drawn collector tank which is produced from a metal plate and may have a sheet-metal base with openings for the flat tubes. Directing elements and/or partition walls may be provided in the collector tank in order to direct the coolant and distribute it to the flat tubes.

The openings in the base preferably correspond to the external dimensions of the flat tubes, and the bases are soldered to the flat tubes, which are plugged into the openings.

Corrugated ribs are preferably provided between the flat tubes, these ribs increasing the heat-transfer surface area and thus improving the exchange of heat.

The coolant used is preferably a liquid, in particular water.

The charge air intercooler is preferably arranged directly in a compressor housing or an intake housing, but may also have a dedicated housing.

In order to provide for optimum charge air flow, at least one charge air tank, through which the charge air flows, is preferably provided.

The invention is explained in detail hereinbelow by way of an exemplary embodiment and with reference to the drawing, in which:

FIG. 1 shows a schematic perspective illustration, in exploded form, of a charge air intercooler according to the invention, without side panels in some areas,

FIG. 2 shows a schematic perspective illustration of the charge air intercooler from FIG. 1 with a fastening plate in the region of the coolant inlet and outlet,

FIG. 3 shows a schematic section, illustrated in detail form, through the charge air intercooler from FIG. 1, and

FIG. 4 shows a schematic section, illustrated in detail form, through a charge air intercooler from the prior art.

A charge air intercooler 1 has a first collector tank 2 comprising a deep-drawn first part 3 with a coolant inlet 4 and a coolant outlet 5 and a flat second part 7 (base) which is provided with slots for flat tubes 6 and via which coolant (in this case water) is fed to, and discharged from, the charge air intercooler 1, as is indicated by arrows.

A partition wall (not illustrated) is provided in the interior of the first collector tank 2, approximately in the center, in order to prevent crossflow of the coolant directly from the coolant inlet 4 to the coolant outlet 5. Arranged between the flat tubes 6, which are plugged into the slots and in which turbulence inserts are arranged, are corrugated ribs 8, for the purpose of increasing the heat-transfer surface area.

A second collector tank 9 is arranged on that side of the flat tubes 6 which is located opposite the first collector tank 2. The second collector tank 9, corresponding to the first collector tank 2, has a deep-drawn first part 10 and a flat second part 11 (base) which is provided with slots for flat tubes 6, it being the case that, rather than having a coolant inlet 4 and coolant outlet 5, the deep-drawn first part 10 merely deflects the coolant from one row of flat tubes to the next row of flat tubes.

Throughout the region between the two bases of the collector tanks 2 and 9, as is indicated by a large arrow in FIG. 1, charge air which is to be cooled flows through the charge air intercooler 1, and in the present case the coolant flows in cross-countercurrent operation essentially perpendicularly to the flow direction of the charge air through the rows of flat tubes.

In order to achieve the highest possible level of efficiency, the height of the charge air channel HL here is approximately 2.5 times the height of the coolant channel HK.

It is the case here, within the production framework, that all the parts of the charge air intercooler 1, once assembled, are soldered together in a single operation.

According to a variant which is not illustrated in the drawing, just a single row of flat tubes is provided. Turbulence inserts are arranged in the flat tubes here, and these ensure better mixing of the coolant.

According to a second variant which is not illustrated in the drawing, corresponding to the first variant, just one row of flat tubes with turbulence inserts is provided, but in this case the flat tubes are subdivided so as to allow cross-countercurrent operation in conjunction with partition walls in the collector tanks.

In the present case, as described in the exemplary embodiment and the variants thereof, such a charge air intercooler is integrated directly in the intake housing, but it is also possible for it to be arranged, for example, in the compressor housing or in a dedicated housing. 

1. A charge air intercooler, in particular for a passenger vehicle, in which charge air can be cooled by a coolant flowing in flow channels, wherein the flow channels for the coolant are formed by flat tubes.
 2. The charge air intercooler as claimed in claim 1, wherein the flat tubes are arranged in at least one row.
 3. The charge air intercooler as claimed in claim 1, wherein two or more rows of flat tubes are provided one behind the other in the flow direction of the charge air.
 4. The charge air intercooler as claimed in claim 1, wherein at least two rows of flat tubes are provided, and flow can take place through these in crosscurrent operation or in cross-counter current operation in relation to the charge air which is to be cooled, and/or in that flow can take place through individual chambers of the flat tubes in crosscurrent operation.
 5. The charge air intercooler as claimed in claim 1, wherein the individual components of the charge air intercooler are soldered together.
 6. The charge air intercooler as claimed in claim 1, wherein turbulence inserts are arranged in the flat tubes.
 7. The charge air intercooler as claimed in claim 1, wherein the flat tubes terminate in at least one collector tank.
 8. The charge air intercooler as claimed in claim 7, wherein the collector tank has a base with openings which correspond to the external dimensions of the flat tubes, and the flat tubes are soldered thereto.
 9. The charge air intercooler as claimed in claim 1, wherein corrugated ribs are provided between the flat tubes.
 10. The charge air intercooler as claimed in claim 1, wherein the coolant is a liquid, in particular water.
 11. The charge air intercooler as claimed in claim 1, wherein the charge air intercooler is arranged in a compressor housing or an intake housing.
 12. The charge air intercooler as claimed in claim 1, further comprising at least one air tank for guiding the charge air.
 13. The charge air intercooler as claimed in claim 1, wherein the ratio of charge air channel height (HL) to coolant channel height (HK) is 1:1 to 10:1, in particular 2:1 to 8:1. 